diff --git a/sys/kern/subr_mbuf.c b/sys/kern/subr_mbuf.c
index 18efe4a9909..97ea5869600 100644
--- a/sys/kern/subr_mbuf.c
+++ b/sys/kern/subr_mbuf.c
@@ -132,7 +132,7 @@ struct mb_pcpu_list {
  * allocatable by the sfbuf allocator (found in uipc_syscalls.c)
  */
 #ifndef NMBCLUSTERS
-#define	NMBCLUSTERS	(1024 + MAXUSERS * 16)
+#define	NMBCLUSTERS	(1024 + MAXUSERS * 64)
 #endif
 #ifndef	NMBUFS
 #define	NMBUFS		(NMBCLUSTERS * 2)